1. Field of the Invention
The present invention relates to silicon oxide on which tannic acid being a polyhydric phenol compound is adsorbed, which is used as a so-called degradation preventive for preventing a thermoplastic resin from being decomposed to decrease in a molecular weight by adding to the thermoplastic resin.
2. Description of the Related Art
In general, thermoplastic resins such as polycarbonate, polyester and polyolefin, particularly polycarbonate base resins are decomposed by hydrolysis caused by moisture for a long period of time or heating in molding to decrease in a molecular weight, and this results in lowering in various dynamic properties. Because of performances thereof, a polycarbonate resin is used in many cases in such uses that heat resistance and mechanical dynamic properties are required. Accordingly, a reduction in the molecular weight caused by a change with the passage of time, heating, kneading and the like not only has caused the use purposes thereof to be lost in many cases but also has made it difficult to recycle the molded articles.